HENRY DEACON 185 



burnt pyrites, "cinder," instead of clay for 

 the absorption of the copper salt in the 

 " Deacon" process. 



No. 1,909. 25th May, 1875. The use of 

 magnesia for a similar purpose. 



No. 2,003. ist June, 1875. The purifica- 

 tion of the hydrochloric acid used in the 

 " Deacon " process from sulphuric acid. 



No. 3,920. iith November, 1875. Im- 

 provements in the apparatus for containing 

 an arrangement of the porous materials used. 



No. 176. 8th July 1876. Deacon's "plus 

 pressure " salt-cake roaster. 



The object of this invention was to make a 

 "close," "blind," or "muffle" furnace, in such 

 a manner that the gases of combustion should 

 exert a pressure around the muffle, and so 

 that there should be no suction of any gases 

 within the muffle, through any defective 

 masonry. 



This was achieved by the patent which 

 claims the novelty of constructing a furnace 

 in such a manner that the fire which is 

 contiguous to the furnace is placed so low in 

 relation to the muffle that the ascending 

 power of the column of hot air over the fire 

 is sufficient so to propel the flame, and other 

 products of combustion through the flues 



